Managing subscriber information

ABSTRACT

A method includes storing subscriber data at one or more locations, and storing, at least one of the one or more locations, one or more rules for managing the subscriber data at least one of the one or more locations. The subscriber data regarding at least one of the one or more locations is managed on the basis of the rules.

The present invention relates to techniques for managing informationregarding a subscriber to a telecommunications network.

When a user terminal attempts to access a telecommunications network, itis normal practice for the telecommunication network to control accessto said telecommunications network on the basis of subscriberinformation associated with said user terminal. Such subscriberinformation may, for example, include personal information, chargingprofile information, and authentication, authorisation and accountinginformation etc.

A register, such as a Home Location Register, is typically used to storesuch subscriber data for a plurality of subscribers. In order to reducethe load on such register, it is known to remove from such registersubscriber data for any subscriber as and when that subscriber has beeninactive for a pre-defined period of time (which operation is known as“cleaning”). There has been identified the problem that such techniquefor cleaning the register is not as efficient as it could be in a systeminvolving different kinds of users.

Also, where there is the possibility that a subscriber may access thetelecommunications network via one of a plurality of different accesstechnologies through a respective application, it is known to provideseveral stand-alone SQL/LDAP servers to provide user access informationfor the respective various access technologies. There has beenidentified the problem that such a system is complex and inefficient interms of database usage.

Furthermore, the inventors have identified a need to more flexiblycontrol calls/sessions, and in particular to provide a more flexiblecharging policy which can be tailored to meet the particularrequirements of any subscriber with a view to making subscription moreattractive to customers. The more flexible management of subscriberprofile information, such as for example charging class information,could be done by each service application processing subscriber profileinformation received from a centralised store of said subscriber profileinformation, but there has been identified the additional problem thatthis would make the applications complex and difficult to maintain.

It is an aim of the present invention to provide one or more techniquesthat at least partly address one or more (but preferably all) of theproblems discussed above.

According to the present invention, there is provided a methodcomprising: storing subscriber data at one or more locations; storing atleast one of said one or more locations one or more rules for managingsaid subscriber data at least one of said one or more locations; andmanaging said subscriber data at least one of said one or more locationson the basis of said rules.

In one embodiment, the method further comprises: receiving a request fordata regarding a first subscriber to a communications network;processing at least one element of said subscriber data for said firstsubscriber on the basis of at least a first rule of said one or morerules and on the basis of a feature of said request so as to produce amodified element of subscriber data; and providing said modified elementof subscriber data to said application. Said at least one element ofdata may specify at least a first value for a parameter, and saidmodified element of data specifies at least a second value for saidparameter different to said at least a first value. Said feature of saidrequest is, for example, selected from the group consisting of: the timeat which the request was made; the identity of an application to whichthe request relates; and the type of service to which the requestrelates.

In one embodiment said request is from a charging system, and theparameter is charging class.

In one embodiment, the method comprises: in response to a change in aparameter, providing subscriber information to an application, whereinthe subscriber information provided to the application is based on saidsubscriber data stored at said one or more locations and at least afirst rule of said one or more rules for modifying said subscriber datain response to said change in a parameter. Said change in a parameteris, for example, selected from the group consisting of: a change in timeand a change in the location of a subscriber.

In one embodiment, the method comprises: controlling retention of saidsubscriber data for a first subscriber at least a first location of saidone or more locations on the basis of at least one first rule of saidone or more rules and on the basis of said subscriber data for saidfirst subscriber. Said subscriber data specifies a subscription type forsaid first subscriber, and said at least one first rule specifies if andwhen said subscriber data for said first subscriber is to be deletedfrom said at least first location on the basis of said subscription typefor said first subscriber. Said subscription type is, for example,selected from the group consisting of: business user, pre-paidsubscriber, telemetric subscriber and low-end user. Said first locationmay be a Home Location Register (HLR), and the method may comprisedeleting said subscriber data for said first subscriber from said HLRbut retaining said subscriber data for said first subscriber at acentral repository, from where it is automatically restored to the HLRwhen an application generates a transaction related to said subscriberdata for said first suscriber.

Initiating said deleting may be done on the basis of said at least onefirst rule and subscriber data for said first subscriber stored at saidcentral repository. For example, said at least one first rule mayspecify deleting said subscriber data for a subscriber of a first typefrom said Home Location Register immediately after each and every time atransaction relating to said subscriber of a first type is completed.

In one embodiment, said subscriber data for a first subscriber is storedat a Home Location Register (HLR), and said at least one first rulespecifies controlling the retention of said subscriber data for asubscriber of a second type at said Home Location Register such thatsaid subscriber data for said subscriber of a second type is not deletedfrom said Home Location Register regardless of how long since the HomeLocation Register last received a request for information regarding saidsubscriber of a second type.

According to the present invention, there is also provided a device,comprising: a first unit configured to store subscriber data; a secondunit configured to store one or more rules for managing said subscriberdata; and a third unit configured to manage said subscriber data on thebasis of said one or more rules.

In one embodiment, the device is configured to: receive a request froman entity for data regarding a first subscriber to a communicationsnetwork; and wherein said third unit is configured to process at leastone element of data from said subscriber data for said first subscriberon the basis of at least one first rule of said one or more rules and onthe basis of a feature of said request so as to produce a modifiedelement of data, and to provide said modified element of data to saidentity. For example, said request may from a charging system, and the atleast one element of data may be charging class.

In one embodiment, the device is configured to: in response to a changein a parameter, provide subscriber information to an application,wherein the subscriber information provided to the application is basedon said subscriber data stored at said first unit and at least a firstrule of said one or more rules for modifying said subscriber data inresponse to said change in a parameter. Said change in a parameter is,for example, selected from the group consisting of: a change in time anda change in the location of a subscriber.

In one embodiment said subscriber data is stored at a plurality of saidfirst units, and wherein said third unit is configured to controlretention at one of said plurality of said first units of saidsubscriber data regarding a first subscriber to a telecommunicationsnetwork on the basis of at least one first rule of said one or morerules and on the basis of said subscriber data for said firstsubscriber. Said plurality of said first units may, for example, includea Home Location Register and a central subscription repository.

According to the present invention, there is also provided a systemcomprising: a first entity configured to store subscriber data for aplurality of subscribers to one or more communications network; and asecond entity configured to implement a service for at least a firstsubscriber on the basis of subscriber information received from saidfirst entity for said at least first subscriber; wherein said firstentity is also configured to store one or more rules for processing saidsubscriber data, and to provide to said second entity subscriberinformation for said at least first subscriber based on said subscriberdata for said at least first subscriber and at least a first rule ofsaid one or more rules.

In one embodiment, the first entity is a central subscriptionrepository, and.or the second entity is configured to implement aCharging System application.

According to the present invention, there is also provided a systemcomprising: a first entity configured to store subscriber data for aplurality of subscribers to a communications network; and a secondentity configured to also store subscriber data for said plurality ofsubscribers; wherein said second entity is configured to control theretention at said first entity of said subscriber data for at least afirst subscriber on the basis of at least one first rule of one or morerules stored at said first entity and on the basis of said subscriberdata for said first subscriber.

In one embodiment, the second entity is a centralised subscriptionrepository, and/or the first entity is an HLR

According to the present invention, there is also provided a computerprogram product comprising program code which when loaded onto acomputer performs the managing of any of the above methods.

According to the present invention, there is also provided a device,comprising: means for storing subscriber data; means for storing one ormore rules for managing said subscriber data; and means for managingsaid subscriber data on the basis of said one or more rules.

According to the present invention, there is also provided a methodcomprising: providing at a single logical entity a source of subscriberinformation relating to controlling access to a network via each of aplurality of wireless access technologies.

In one embodiment, the method comprises obtaining from said singlelogical entity subscriber information relating to controlling access toa network via a first access technology; and obtaining from said singlelogical entity subscriber information relating to controlling access toa network via a second access technology different to said first accesstechnology. The single logical entity may, for example, function as aHome Location Register. Said subscriber information may, for example,include authentication, authorisation and accounting information.

According to the present invention, there is also provided a devicewhich is configured to store subscriber information relating tocontrolling access to a network via each of a plurality of accesstechnologies; and upon request to provide selected data from said storedinformation to an application for implementing a service relating to oneof said plurality of access technologies.

In one embodiment, the device functions as a Home Location Register,and/or said subscriber information includes authentication,authorisation and accounting information.

According to the present invention, there is also provided a devicewhich is configured to participate in controlling access by a subscriberto a network for both access via a first access technology and accessvia a second access technology, and to access a single logical entityfor subscriber information relating to control of said access regardlessof whether the access is via said first access technology or via saidsecond access technology.

In one embodiment, the device is located at a Serving GPRS Support Node(SGSN), and/or the single logical entity is a Home Location Register.

Embodiments of the present invention are described in more detailhereunder, by way of example only, with reference to the accompanyingdrawings, in which:

FIG. 1 shows an example of a system architecture to which the presentinvention is applicable;

FIG. 2 illustrates an apparatus for storing and providing subscriberinformation according to an embodiment of the present invention;

FIG. 3 illustrates an apparatus for controlling the maintenance ofsubscriber information according to an embodiment of the presentinvention;

FIG. 4 illustrates an operation of a CSR according to an embodiment ofthe present invention;

FIG. 5 illustrates an operation of an HLR according to an embodiment ofthe present invention.

FIG. 6 illustrates an operation of a SGSN according to an embodiment ofthe present invention; and

FIG. 7 illustrates a method of controlling the retention of subscriberinformation at an HLR according to an embodiment of the presentinvention;

With reference to FIG. 1, a mobile station 10 may attempt to access afirst mobile network 1. The mobile station 10 may, for example, wish toconduct a call with another mobile station associated with the samemobile network 1 or with another mobile network, or to obtaininformation from a remote server accessible via the mobile network andone or more other networks such as the internet or Public SwitchedTelephone Network (PSTN). The mobile station 10 sends signalling to aGPRS Support Node (SGSN) 2 via a base station 8 and a Radio NetworkController (RNC) 6. The signalling includes a request for a particularservice (such as a call to a remote party) and includes informationidentifying the mobile station 10.

One or more applications are typically used for implementing therequested service. The one or more Applications typically requiresubscriber information in order to implement the service. For example, aCharging System application 38 may need to be provided with chargingclass information from the subscriber profile.

Information relating to subscribers, such as access, authorisation andaccounting (AAA) information etc., may be stored at a centralisedsubscription repository (CSR) (36). The central subscription repository(CSR) 36, is (i) accessible by control entities of a plurality of accessnetworks, and/or (ii) holds subscriber data for a plurality of differentapplications, including those normally serviced by a HLR.

The Charging System application 38 accesses the CSR 36 for the chargingclass information it requires.

FIG. 2 illustrates a device according to an embodiment of the presentinvention for locating at CSR 36.

The device illustrated in FIG. 2 includes a Subscriber Database 40storing subscriber profile data, a Rule Database 42 and a Rule Engine44. At step (1), the CSR 36 receives a request from an application forsubscriber profile information associated with the mobile station 10requesting the service. At step (2), subscriber profile data is fetchedfrom the Subscriber Database 40. At step (3), one or more profilemanipulating rules for manipulating said subscriber profile data arefetched from the Rule Database 42. At step (4), the Rule Engine 44processes the subscriber profile data fetched from the SubscriberDatabase 40 in accordance with the one or more profile manipulatingrules fetched from the Rule Database 42. The functionality of the RuleEngine 44 could be implemented by software.

With reference to the Charging System application 38 mentioned above,there may, for example, be a rule that the operator of mobile network 1does not make any charge for calls made by the subscriber on his/herbirthday. The Rule may take the form “IF birthday THEN ChargingClass=Free”. The date of the birthday of the subscriber is specified inthe subscriber profile data maintained at the Subscriber Database 40.The subscriber profile stored at the Subscriber Database also specifiesa default value for the Charging Class. For example, it might beCharging Class=Business. When it is the subscriber's birthday, the ruleengine 44 processes the default value according to the above-mentionedrule, and provides the Charging System Application 38 with theinformation that the Charging Class=Free. When another rule applies tothe charging class, the rule engine 44 again processes the default valueaccordingly, and provides the application with the processed value forthe Charging Class. Where there is no applicable rule relating to theCharging Class, the rule engine 44 provides the Application with theDefault Value for the Charging Class.

The above-described operation of the device of FIG. 2 for the ChargingSystem application 38 example is illustrated in FIG. 4.

There could, for example, also be other rules that are based on thetime/date of the query from an Application to the CSR 36 for thesubscriber profile. There could also be one or more rules that are basedon the identity of the Application making the query for the subscriberprofile, and/or one or more rules that are based on the identity of theservice to which the Application making the query for the subscriberprofile is related.

In the example described above, the device of FIG. 2 provides subscriberinformation to the Charging System application 38 in response to arequest from the Charging System application. In one variation, thedevice of FIG. 2 may voluntarily provide subscriber information to anApplication even without any such request. For example, the servicesavailable to a subscriber at any given time may depend on the locationof the subscriber at such time, and there could be a rule that specifiesproviding modified available service data to an Application in responseto a certain change in the present location of the subscriber asspecified in the subscriber profile data for said subscriber atsubscriber database 40. Similarly, there could be a rule that specifiesproviding other modified subscriber profile data to an Application basedon the time or present location of the subscriber. Such rules could begeneral rules for all subscribers. For example, for a given area, theavailable service data sent to the Application could be modified in thesame way for any subscriber specified in his/her subscriber profilestored at database 40 to have moved into such area.

In this way, an Application (such as Charging System Application 38) canoperate in accordance with any rules that the operator of the wirelessaccess network might wish to apply without any need for the Applicationto be specially modified, which special modification could make theApplication unnecessarily complex and difficult to maintain. In otherwords, the Application can use the subscriber profile as received fromthe CSR 36 without having to make complex decisions about how to applythe profile. Also, the maintenance of the subscriber profile data ismade simple.

Management functionality is provided to create and maintain the profilemanipulation rules.

According to one variation of the above-described technique, the deviceillustrated in FIG. 2 could instead be located at Home Location Register4 (and/or Home Location Register 22). If first mobile network 1 is thehome network for mobile station 10, the Charging System application 38would access the Home Location Register 4 associated with the firstmobile network for the subscriber information it requires. If, forexample, second mobile network 3 is the home network for mobile station10, the Charging System application 38 would access via the internet 18the Home Location Register 22 associated with the second mobile network3 for the subscriber information it requires.

According to an embodiment of another aspect of the present invention,the HLR 4 is configured to be a source of information for service,access, authentication, authorisation and accounting information forcalls/sessions based on any one of a plurality of wireless accesstechnologies.

An example of service type information is information as to the closestnetwork element (NE) that provides the user-requested service based onthe user/access point location. An example of access information isinformation as to whether an IP-address can be given for some xDSLline-id. This is closely related to authorisation.

In one example, the SGSN 2 is configured to offer RADIUS serverfunctionality not only for GPRS access (such as access by a GPRS mobilestation 10 via a GPRS base station 8) but also for access (by a secondtype of mobile station 14 via a second type of base station 12) to thenetwork 1 according to one or more of the wireless access technologieslisted below, and/or one or more non-wireless technologies.

Broadband Wireless Access (BWA)

Worldwide Interoperability for Microwave Access (WiMax) Internet—HighSpeed Packet Access (I-HSPA)

3.9G/LTE (and additionally, the next generation of 3G technologies,3.9G, also called UTRAN LTE (Universal Terrestrial Radio Access NetworkLong Term Evolution) or Super 3G. Its peak data rates are targeted toreach up to 100 Mbps in the downlink and 50 Mbps in the uplink.Any NGN technology (as specified by ETSI TISPAN specifications e.g. ES282 001, where ETSI is the European Telecommunication StandardsInstitute and TISPAN is an acronym for TIPHON (Telecommunications andInternet Protocol Harmonization over Networks) and SPAN (Services andProtocols for Advanced Networks).High Speed Packet Access (HSPA): A nomenclature for developmentsencompassing both directions of information transmission—the downlink(HSDPA) and the uplink (HSUPA) directions. HSPA is an enhancement toUMTS and offers a successful combination of spectral efficiency (4-5times that of UMTS), high speed data throughput (eventually averaging550-1100 Kbps on the downlink), and low latency (less than 100 ms), thusenabling true mass market mobile broadband. HSPA also lowers the costper bit, enabling cost-effective, rich multimedia services.HSPA Evolution (HSPA+): HSPA+ is a study item of 3GPP to enableoperators to capitalize on existing RAN infrastructure investments byfurther improving the radio performance of HSPA, as well as leveragingthe use of the SAE (see below) core with the current radio interface in2×5 MHz spectrum. HSPA+ is an enhancement where simplifications andrationalizations agreed upon for LTE/SAE (see below) are partiallyapplied to the HSPA system with a vision of providing full servicedelivery through the Packet Switched (PS) Domain.System Architecture Evolution (SAE): The 3GPP work item for developing aframework for a higher-data-rate, lower-latency, packet-optimized systemthat supports multiple radio access technologies with a focus on thepacket-switched domain to support voice services. The main drivers forthe network evolution are: to be able to meet the targets for theevolution of the radio-interface (LTE) (see below), to enable evolutiontowards an All-IP Network, and to support mobility and servicecontinuity between heterogeneous access networks.Long Term Evolution (LTE): The 3GPP work item on the long term evolution(LTE) of UTRAN (Universal Terrestrial Radio Access Network) or theAir-Interface Evolution to develop a framework for a high-data-rate,low-latency and packet-optimized radio-access technology.

Furthermore this technique also suits Broadband wireline access such asxDSL. In xDSL, access information would be relevant for DHCP purposes.

The data that is stored in the HLR 4 is used by the DHCP/RADIUS serveror any other server such as NASS (Network Attachment SubSystem) tovalidate, authorize, authenticate, grant permission or used foraccounting purposes. NASS could use the stored data for resourceadmission control purposes (RACS as specified by TISPAN) or for TISPANuser profiles that can be used by applications/service layer/servicecontrol subsystem. In TISPAN specifications, the HLR would act as PDBF(Profile Database Functions).

This operation of the SGSN 2 is illustrated in FIG. 6, and thisoperation of the HLR 4 is illustrated in FIG. 5.

The DHCP/AAA/NASS functionality could be integrated to the SGSN 2 (or anInternet Service Node (ISN) (or similar node). The above-describedintegrated technique has the advantage that the SGSN 2 only needs to beable to connect to the HLR 4 to obtain AAA data for any one of aplurality of wireless access technologies, the configuration for settingup other wireless access technologies (such as BWA) is simplified, anddatabase usage is streamlined as all the required information can beaccessed from the HLR 4.

In one embodiment, the SGSN with integrated DHCP/AAA/NASS functionalityreceives all the necessary information from the HLR relating to theparticular user. The database (DB) load is thereby significantlydecreased. Also this would simplify the SGSN as it would need to supportonly one interface (i/f) to the database. The interface could, forexample, be one that facilitates access to Structured Query Language(SQL)/Lightweight Directory Access Protocol (LDAP) database(s) to obtainsuch data.

Furthermore, where HLR 4 is used as a source of subscriber profileinformation, a centralised subscriber data repository (CSR) 36 is alsoprovided in addition to the HLR 4. The subscriber profile data that isstored at the Subscriber Database of the HLR 4 is also stored at the CSR36. The HLR can thus be cleaned of all data other than that which it isconsidered efficient to retain at the HLR 4 whilst retaining a separatestore of such information at the CSR with which to replenish HLR 4, whennecessary (such as when a subscriber becomes newly active after aprolonged period of inactivity). The decision as to when to clean theHLR 4 of subscriber data for a given subscriber is based on thesubscriber type/class specified in the subscriber profile for thesubscriber, and rules defined by the network operator. The following areprovided as examples:

A. Some subscribers may be classed as business users, and there may be arule that any business user is never to have his/her subscriber profileautomatically cleaned from the HLR regardless of how long he/she may beinactive (i.e. regardless of how much time has passed since the lasttime the HLR received a request for the subscriber profile for thesubscriber).

B. Some subscribers might be classed as pre-paid subscribers and somesubscribers might be classed as contract subscribers, and the rulesmight specify different, respective periods of inactivity after whicheach of these two types of subscribers are to have their data cleanedfrom the HLR 4. For example, the rules might specify pre-paidsubscribers are to have their data cleaned from the HLR after two weeksof inactivity, but specify a different period of inactivity for contractsubscribers.

C. Some subscribers might be classified as telemetric subscribers, andthe rules might specify that the subscriber profile associated with sucha subscriber is to be automatically cleaned from the HLR immediatelyafter the end of each and every transaction involving such subscriber.

D. An operator might offer different types of subscriptions at differentcosts. Subscribers having a low-cost might be classed as low-end users,and the rules might specify that the subscriber profile for any suchlow-end user is to be cleaned from the HLR 4 after a shorter period ofinactivity than for other users having a higher cost subscription. Forexample, the rules might specify that a low-end user is to have his/herdata automatically cleaned from the HLR after only one day ofinactivity.

Another possibility is to specify on an individual basis how cleaningshould be performed. This could be done by including in the subscriberprofile stored at the CSR 36 one or more special data fields thatexplicitly specify if and how automatic cleaning should be performed forthe respective subscriber.

In each case where a subscriber profile for a subscriber isautomatically cleaned from the HLR 4, said subscriber profile isretained at the CSR 36 and is restored to the HLR the next time atransaction is initiated by said subscriber.

The above-described technique is illustrated in FIG. 7.

The functionality of the CSR 36 for such a technique is illustrated inmore detail in FIG. 3. It includes a subscriber profile database 54 forstoring subscriber profile data, a cleaning rule database 52 for storingone or more cleaning rules that can be entered via a user interface (notshown), and a processor 50 for making a decision as to when to cleansubscriber profile data from the HLR 4 on the basis of the subscriberprofile data, and where applicable, also on the basis of the applicablecleaning rule stored at cleaning rule database 52. For example, wherethe profile of a given subscriber specifies explicitly (in said one ormore above-mentioned special data fields) how cleaning should beperformed for said subscriber, the processor 50 controls the automaticcleaning of data from the HLR 4 accordingly. Where there is no suchexplicit information included in the profile of a subscriber, theprocessor 50 controls the automatic cleaning of data from the HLR 4 onthe basis of the subscriber class specified for the subscriber in thesubscriber profile and on the basis of the cleaning rule specified forsuch class in the cleaning rule database 52. This functionality of theCSR could be implemented by software.

The dotted line between the CSR 36 and the HLR 4 in FIG. 1 indicates thelogical connection between the CSR 36 and the HLR 4. The CSR may storesubscriber profile data for more than one access network. For example,with reference to FIG. 1, the CSR 36 may also store subscriber profiledata for a second wireless access network 3, including one or more basestations 28, 32, a controlling entity 24 and a Home Location Register22. The CSR 36 may also function to control cleaning of the HLR 22 ofthis second wireless access network 3 in the same way as described abovefor the first wireless access network 1. Fort example, the same logicalconnection exists between the CSR 36 and the second HLR 22, asillustrated by the dotted line in FIG. 1.

In one embodiment, the HLR does not need to inform the CSR about thecompletion of a transaction; the HLR only submits a query to the CSRwhen it does not already have all the necessary subscriber data, andupdates the CSR when necessary. In one embodiment, the HLR is adataless-type HLR, and it does not permanently store any subscriberinformation, but submits a query to the CSR for every singletransaction. In another embodiment, the HLR is a dataful-type HLR, andit will be apparent to the skilled person what mechanisms would berequired to ensure consistency between the CSR and the HLR.

The instruction from the CSR to the HLR to clean a subscriber could beimplemented in a number of ways. One example would be a simple commandprotocol on top of Lightweight Data Access Protocol (LDAP) or SimpleObject Access Protocol (SOAP).

With the above-described technique, cleaning of the HLR 4 can be carriedout effectively. Where less important data is cleaned more quickly fromthe HLR 4, extra capacity is released to retain more critical subscriberdata at the HLR for a longer time.

Appropriately adapted computer program product may be used forimplementing any of the techniques described above. The program codeproduct may be stored on and provided by means of a carrier medium suchas a carrier disc, card or tape. Another possibility is to download theprogram code product via a data network.

The applicant draws attention to the fact that the present invention mayinclude any feature or combination of features disclosed herein eitherimplicitly or explicitly or any generalisation thereof, withoutlimitation to the scope of any definitions set out above. In view of theforegoing description it will be evident to a person skilled in the artthat various modifications may be made within the scope of theinvention.

1. A method comprising: storing subscriber data at one or morelocations; storing at least one of said one or more locations one ormore rules for managing said subscriber data at least one of said one ormore locations; and managing said subscriber data at least one of saidone or more locations on the basis of said rules.
 2. A method accordingto claim 1, further comprising: receiving a request for data regarding afirst subscriber to a communications network; processing at least oneelement of said subscriber data for said first subscriber on the basisof at least a first rule of said one or more rules and on the basis of afeature of said request so as to produce a modified element ofsubscriber data; and providing said modified element of subscriber datato said application.
 3. A method according to claim 2, wherein said atleast one element of data specifies at least a first value for aparameter, and said modified element of data specifies at least a secondvalue for said parameter different to said at least a first value.
 4. Amethod according to claim 2, wherein said feature of said request isselected from the group consisting of: the time at which the request wasmade; the identity of an application to which the request relates; andthe type of service to which the request relates.
 5. A method accordingto claim 3, wherein said request is from a charging system, and theparameter is charging class.
 6. A method according to claim 1,comprising: in response to a change in a parameter, providing subscriberinformation to an application, wherein the subscriber informationprovided to the application is based on said subscriber data stored atsaid one or more locations and at least a first rule of said one or morerules for modifying said subscriber data in response to said change in aparameter.
 7. A method according to claim 6, wherein said change in aparameter is selected from the group consisting of: a change in time anda change in the location of a subscriber.
 8. A method according to claim1, comprising: controlling retention of said subscriber data for a firstsubscriber at least a first location of said one or more locations onthe basis of at least one first rule of said one or more rules and onthe basis of said subscriber data for said first subscriber.
 9. A methodaccording to claim 8, wherein said subscriber data specifies asubscription type for said first subscriber, and wherein said at leastone first rule specifies if and when said subscriber data for said firstsubscriber is to be deleted from said at least first location on thebasis of said subscription type for said first subscriber.
 10. A methodaccording to claim 9, wherein said subscription type is selected fromthe group consisting of: business user, pre-paid subscriber, telemetricsubscriber and low-end user.
 11. A method according to claim 9, whereinsaid first location is a Home Location Register (HLR), and comprisingdeleting said subscriber data for said first subscriber from said HLRbut retaining said subscriber data for said first subscriber at acentral repository, from where it is automatically restored to the HLRwhen an application generates a transaction related to said subscriberdata for said first suscriber.
 12. A method according to claim 11further comprising initiating said deleting on the basis of said atleast one first rule and subscriber data for said first subscriberstored at said central repository.
 13. A method according to claim 10,wherein said at least one first rule specifies deleting said subscriberdata for a subscriber of a first type from said Home Location Registerimmediately after each and every time a transaction relating to saidsubscriber of a first type is completed.
 14. A method according to claim7, wherein said subscriber data for a first subscriber is stored at aHome Location Register (HLR), and wherein said at least one first rulespecifies controlling the retention of said subscriber data for asubscriber of a second type at said Home Location Register such thatsaid subscriber data for said subscriber of a second type is not deletedfrom said Home Location Register regardless of how long since the HomeLocation Register last received a request for information regarding saidsubscriber of a second type.
 15. A device, comprising: a first unitconfigured to store subscriber data; a second unit configured to storeone or more rules for managing said subscriber data; and a third unitconfigured to manage said subscriber data on the basis of said one ormore rules.
 16. A device according to claim 15, which is configured to:receive a request from an entity for data regarding a first subscriberto a communications network; and wherein said third unit is configuredto process at least one element of data from said subscriber data forsaid first subscriber on the basis of at least one first rule of saidone or more rules and on the basis of a feature of said request so as toproduce a modified element of data, and to provide said modified elementof data to said entity.
 17. A device according to claim 16, wherein saidrequest is from a charging system, and the at least one element of datais charging class.
 18. A device according to claim 15, which isconfigured to: in response to a change in a parameter, providesubscriber information to an application, wherein the subscriberinformation provided to the application is based on said subscriber datastored at said first unit and at least a first rule of said one or morerules for modifying said subscriber data in response to said change in aparameter.
 19. A device according to claim 18, wherein said change in aparameter is selected from the group consisting of: a change in time anda change in the location of a subscriber.
 20. A device according toclaim 15, wherein said subscriber data is stored at a plurality of saidfirst units, and wherein said third unit is configured to controlretention at one of said plurality of said first units of saidsubscriber data regarding a first subscriber to a telecommunicationsnetwork on the basis of at least one first rule of said one or morerules and on the basis of said subscriber data for said firstsubscriber.
 21. A device according to claim 20, wherein said pluralityof said first units includes a Home Location Register and a centralsubscription repository.
 22. A system comprising: a first entityconfigured to store subscriber data for a plurality of subscribers toone or more communications network; and a second entity configured toimplement a service for at least a first subscriber on the basis ofsubscriber information received from said first entity for said at leastfirst subscriber; wherein said first entity is also configured to storeone or more rules for processing said subscriber data, and to provide tosaid second entity subscriber information for said at least firstsubscriber based on said subscriber data for said at least firstsubscriber and at least a first rule of said one or more rules.
 23. Asystem according to claim 22, wherein the first entity is a centralsubscription repository.
 24. A system according to claim 22, wherein thesecond entity is configured to implement a Charging System application.25. A system comprising: a first entity configured to store subscriberdata for a plurality of subscribers to a communications network; and asecond entity configured to also store subscriber data for saidplurality of subscribers; wherein said second entity is configured tocontrol the retention at said first entity of said subscriber data forat least a first subscriber on the basis of at least one first rule ofone or more rules stored at said first entity and on the basis of saidsubscriber data for said first subscriber.
 26. A system according toclaim 25, wherein the second entity is a centralised subscriptionrepository.
 27. A system according to claim 25, wherein the first entityis an HLR
 28. A computer program product comprising program code whichwhen loaded onto a computer performs the managing of the method ofclaim
 1. 29. A device, comprising: means for storing subscriber data;means for storing one or more rules for managing said subscriber data;and means for managing said subscriber data on the basis of said one ormore rules.
 30. A method comprising: providing at a single logicalentity a source of subscriber information relating to controlling accessto a network via each of a plurality of wireless access technologies.31. A method according to claim 30, comprising: obtaining from saidsingle logical entity subscriber information relating to controllingaccess to a network via a first access technology; and obtaining fromsaid single logical entity subscriber information relating tocontrolling access to a network via a second access technology differentto said first access technology.
 32. A method according to claim 30,wherein the single logical entity functions as a Home Location Register.33. A method according to claim 30, wherein said subscriber informationincludes authentication, authorisation and accounting information.
 34. Adevice which is configured to store subscriber information relating tocontrolling access to a network via each of a plurality of accesstechnologies; and upon request to provide selected data from said storedinformation to an application for implementing a service relating to oneof said plurality of access technologies.
 35. A device according toclaim 34, which functions as a Home Location Register.
 36. A deviceaccording to claim 34, wherein said subscriber information includesauthentication, authorisation and accounting information.
 37. A devicewhich is configured to participate in controlling access by a subscriberto a network for both access via a first access technology and accessvia a second access technology, and to access a single logical entityfor subscriber information relating to control of said access regardlessof whether the access is via said first access technology or via saidsecond access technology.
 38. A device according to claim 37, which islocated at a Serving GPRS Support Node (SGSN).
 39. A device according toclaim 37, wherein the single logical entity is a Home Location Register.